I am confused about this term. I’ve been told it can refer to either a type of topology or simply a type of connection.
Both.
Many components have XLR (balanced) connectors.
Many of those components have XLR connectors for convenience, but they are not balanced circuits.
Can you connect those two components? Absolutely.
The La Voce S3 Discrete DAC specs state "XLR balanced asymmetrical", which means it is not balanced. The XLR connectors are for convenience if connecting to a preamp or integrated amplifier with XLR inputs. The JOTUNHEIM specs state it is "inherently differentially" balanced. Regardless, you can connect them, you just won’t be taking advantage of better noise rejection provided by a differentially balanced DAC. Will you hear it? Maybe not. You know a differentially balanced DAC module can be added to the JOTUNHEIM, right?